Cath Lab Digest

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Index: Ostomy Wound Manage. 2012;58(4):50–69.

Abstract

  Negative pressure wound therapy (NPWT) is used extensively in the management of acute and chronic wounds, but concerns persist about its efficacy, effectiveness, and safety. Available guidelines and algorithms are wound type-specific, not evidence-based, and many lack clearly described relative and absolute contraindications and stop criteria. The purpose of this research was to: 1) develop evidence-based algorithms for the safe use of NPWT in adults with acute and chronic wounds by nonwound expert clinicians, and 2) obtain face validity for the algorithms. Using NPWT meta-analyses and systematic reviews (n = 10), NPWT guidelines of care (n = 12), general evidence-based guidelines of wound care (n = 11), and a framework for transitioning between moisture-retentive and NPWT care (n = 1), a set of three algorithms was developed.

Literature-based validity for each of the 39 discreet algorithm steps/decision points was obtained by reviewing best available evidence from systematic literature reviews (n = 331 publications) and abstraction of all NPWT-relevant publications (n = 182) using the patient-oriented Strength of Recommendation (SORT) taxonomy. Of the 182 NPWT studies abstracted, 25 met criteria for level 1 and 2 evidence but only one general assessment step had both level 1 evidence and an “A” strength of recommendation. Next, an Institutional Review Board-approved, cross-sectional mixed methods survey design face validation pilot study was conducted to solicit comments on, and rate the validity of, the 51 discreet algorithm-related statements, including the 39 decisions/steps. Twelve (12) of the 15 invited interdisciplinary wound experts agreed to participate. The overall algorithm content validity index (CVI) was high (0.96 out of 1). Helpful design suggestions to ensure safe use were made, and participants suggested an examination of commonly used wound definitions in follow-up studies. Results of the literature-based face validation confirm that the evidence base for using NPWT remains limited, especially for chronic wounds, and that safety guidance may be affected by the fact that evidence-based ratings cannot accurately reflect relative or absolute product contraindications because they simply are not included in clinical studies. These findings, the positive expert panel comments, and the high CVI confirm the need for an algorithm with explicit NPWT start-and-stop criteria and suggest that follow-up content and construct validation of these algorithms is warranted.

Keywords: wounds, algorithms, negative pressure wound therapy, validation studies, evidence-based medicine/classification

Potential Conflicts of Interest: This study was supported by a research grant from ConvaTec, Inc (Skillman, NJ). The study was conducted, the data analyzed, and the manuscript written by the authors, who are responsible for the content of the publication. The authors do not have a financial interest in any of the products discussed.

Introduction

  Ever since devices to replace improvised systems for the removal and collection of excess wound exudate¹ became commercially available, negative pressure wound therapy (NPWT) systems have been widely used. Initially, only one type of NPWT system was marketed by a single manufacturer, but recently many other NPWT devices have been introduced into the healthcare professional marketplace.

  Major impetus for generating a new perspective on NPWT usage are its clinical cost and limited knowledge about its cost effectiveness for the wide variety of clinical indications.² General evidence to substantiate current indications and contraindications for use is limited and sometimes contradictory.